Given the introduction of https://www.mediawiki.org/wiki/Wikimedia_Apps/Synced_Reading_Lists to the mobile apps, I'd like to explore what's needed to get this working on web (desktop and mobile).
I have some old mocks for how that feature might work.
It presents a challenge for skin development, so it may be of interest for those who write skins. Maybe we can tease out some good best practices for integrating with multiple skins.
Feasiblity study
The API is tailored specifically for apps where there is a local cache/state. A few API methods will be needed to make it possible for this to be out for web, where there is no state and each resource should have a URI (see subtasks)
@Jdlrobson built out a proof of concept, based on some old mocks/components. It is available as a gadget that you can copy and paste into your user vector.js (or mobile.js):
importScript('User:Jdlrobson/script-reading-lists.js');
Demo: